The present invention relates to a brake arrangement, especially to a disk brake for motor vehicles with brake pads guided in a brake caliper on both sides of a brake disk which are operatively connected with hydraulically actuatable actuating pistons.
Disk brakes can tend to squeaking during the braking operation which is caused essentially by an oscillating movement of the brake caliper as well as of the brake pads. Vibrations may occur at the brake arrangement as a result of these movements which radiate a sound that is noticeable to the human ear as so-called "squeaking."
The present invention is concerned with the task to suppress a brake squeaking during an actuation.
The underlying problems are solved according to the present invention in that each actuating piston includes a bore facing the brake pad, in which a cylindrically shaped insert member is arranged that includes a flange covering the piston end-face and is held with a radial and axial play with respect to the inner circumference and the bottom surface of the bore.
The principal advantages achieved with the present invention reside in that a brake squeaking is precluded by a vibration reduction and by a damping by means of a structurally simple part which can be inserted into a bore of the actuating piston that is already present for the most part. This damping takes place essentially by a frictional connection between the insert member and the piston as well as between the insert member and the brake pad whereby owing to the insert member loosely seated in the bore of the actuating piston, the frequency of the oscillation or vibration energy is converted during the braking operation as a result of a sudden abutment at the inner circumferential surface of the piston from the squeaking frequency into a broad band energy with low oscillation or vibration amplitude. Furthermore, a counter-force is exerted on the brake pads by the displaced masses in the actuating pistons.